* [PATCH v3 1/2] UefiPayloadPkg: Implement a new SerialPortLib instance
@ 2022-07-21 9:14 kavya
2022-07-21 9:14 ` [PATCH v3 2/2] UefiPayloadPkg: Allow DxeMain.inf to consume the new SerialPortLib kavya
2022-07-21 9:18 ` [PATCH v3 1/2] UefiPayloadPkg: Implement a new SerialPortLib instance Ni, Ray
0 siblings, 2 replies; 3+ messages in thread
From: kavya @ 2022-07-21 9:14 UTC (permalink / raw)
To: devel; +Cc: Kavya, Guo Dong, Ray Ni, Sean Rhodes, Gua Guo
Add new Serial port library instance that consumes the HOB defined
in MdeModulePkg/Include/UniversalPayload/SerialPortInfo.h to support
multiple UART's.
Cc: Guo Dong <guo.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Sean Rhodes <sean@starlabs.systems>
Cc: Gua Guo <gua.guo@intel.com>
Signed-off-by: Kavya <k.kavyax.sravanthi@intel.com>
---
UefiPayloadPkg/Library/BaseSerialPortLibHob/BaseSerialPortLibHob.c | 814 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
UefiPayloadPkg/Library/BaseSerialPortLibHob/BaseSerialPortLibHob.inf | 40 ++++++++++++++++++++++++++++++++++++++++
2 files changed, 854 insertions(+)
diff --git a/UefiPayloadPkg/Library/BaseSerialPortLibHob/BaseSerialPortLibHob.c b/UefiPayloadPkg/Library/BaseSerialPortLibHob/BaseSerialPortLibHob.c
new file mode 100644
index 0000000000..13eddf0934
--- /dev/null
+++ b/UefiPayloadPkg/Library/BaseSerialPortLibHob/BaseSerialPortLibHob.c
@@ -0,0 +1,814 @@
+/** @file
+ UART Serial Port library functions.
+
+ Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
+ SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+#include <PiDxe.h>
+#include <Base.h>
+#include <Library/PcdLib.h>
+#include <Library/IoLib.h>
+#include <Library/BaseLib.h>
+#include <Library/HobLib.h>
+#include <Library/TimerLib.h>
+#include <Library/DebugLib.h>
+#include <Library/MemoryAllocationLib.h>
+#include <Protocol/SerialIo.h>
+#include <UniversalPayload/SerialPortInfo.h>
+
+//
+// 16550 UART register offsets and bitfields
+//
+#define R_UART_RXBUF 0 // LCR_DLAB = 0
+#define R_UART_TXBUF 0 // LCR_DLAB = 0
+#define R_UART_BAUD_LOW 0 // LCR_DLAB = 1
+#define R_UART_BAUD_HIGH 1 // LCR_DLAB = 1
+#define R_UART_IER 1 // LCR_DLAB = 0
+#define R_UART_FCR 2
+#define B_UART_FCR_FIFOE BIT0
+#define B_UART_FCR_FIFO64 BIT5
+#define R_UART_LCR 3
+#define B_UART_LCR_DLAB BIT7
+#define R_UART_MCR 4
+#define B_UART_MCR_DTRC BIT0
+#define B_UART_MCR_RTS BIT1
+#define R_UART_LSR 5
+#define B_UART_LSR_RXRDY BIT0
+#define B_UART_LSR_TXRDY BIT5
+#define B_UART_LSR_TEMT BIT6
+#define R_UART_MSR 6
+#define B_UART_MSR_CTS BIT4
+#define B_UART_MSR_DSR BIT5
+#define B_UART_MSR_RI BIT6
+#define B_UART_MSR_DCD BIT7
+
+typedef struct {
+ UINTN BaseAddress;
+ BOOLEAN UseMmio;
+ UINT32 BaudRate;
+ UINT8 RegisterStride;
+} UART_INFO;
+
+UART_INFO **mUartInfo;
+UINT8 mUartCount;
+
+/**
+ Reads an 8-bit register. If UseMmio is TRUE, then the value is read from
+ MMIO space. If UseMmio is FALSE, then the value is read from I/O space. The
+ parameter Offset is added to the base address of the register.
+
+ @param Base The base address register of UART device.
+ @param Offset The offset of the register to read.
+ @param UseMmio Check if value has to be read from MMIO space or IO space.
+ @param RegisterStride Number of bytes between registers in serial device.
+
+ @return The value read from the register.
+
+**/
+UINT8
+SerialPortReadRegister (
+ UINTN Base,
+ UINTN Offset,
+ BOOLEAN UseMmio,
+ UINT8 RegisterStride
+ )
+{
+ if (UseMmio) {
+ return MmioRead8 (Base + Offset * RegisterStride);
+ } else {
+ return IoRead8 (Base + Offset * RegisterStride);
+ }
+}
+
+/**
+ Writes an 8-bit register.. If UseMmio is TRUE, then the value is written to
+ MMIO space. If UseMmio is FALSE, then the value is written to I/O space. The
+ parameter Offset is added to the base address of the registers.
+
+ @param Base The base address register of UART device.
+ @param Offset The offset of the register to write.
+ @param Value Value to be written.
+ @param UseMmio Check if value has to be written to MMIO space or IO space.
+ @param RegisterStride Number of bytes between registers in serial device.
+
+ @return The value written to the register.
+
+**/
+UINT8
+SerialPortWriteRegister (
+ UINTN Base,
+ UINTN Offset,
+ UINT8 Value,
+ BOOLEAN UseMmio,
+ UINT8 RegisterStride
+ )
+{
+ if (UseMmio) {
+ return MmioWrite8 (Base + Offset * RegisterStride, Value);
+ } else {
+ return IoWrite8 (Base + Offset * RegisterStride, Value);
+ }
+}
+
+/**
+ Initialize the serial device hardware.
+
+ If no initialization is required, then return RETURN_SUCCESS.
+ If the serial device was successfully initialized, then return RETURN_SUCCESS.
+ If the serial device could not be initialized, then return RETURN_DEVICE_ERROR.
+
+ @retval RETURN_SUCCESS The serial device was initialized.
+ @retval RETURN_DEVICE_ERROR The serial device could not be initialized.
+
+**/
+RETURN_STATUS
+EFIAPI
+SerialPortInitialize (
+ VOID
+ )
+{
+ UNIVERSAL_PAYLOAD_SERIAL_PORT_INFO *SerialPortInfo;
+ EFI_HOB_GUID_TYPE *GuidHob;
+ UINTN SerialRegisterBase;
+ UINT8 RegisterStride;
+ UINT32 Divisor;
+ UINT32 CurrentDivisor;
+ UINT32 BaudRate;
+ BOOLEAN Initialized;
+ BOOLEAN MmioEnable;
+ UINT8 Index;
+ UINT8 Count;
+
+ Count = 0;
+
+ GuidHob = GetFirstGuidHob (&gUniversalPayloadSerialPortInfoGuid);
+ while (GuidHob != NULL) {
+ Count++;
+ GuidHob = GET_NEXT_HOB (GuidHob);
+ GuidHob = GetNextGuidHob (&gUniversalPayloadSerialPortInfoGuid, GuidHob);
+ }
+
+ mUartCount = Count;
+
+ mUartInfo = (UART_INFO **)AllocateZeroPool (sizeof (UART_INFO *) * Count);
+ ASSERT (mUartInfo != NULL);
+
+ for (Index = 0; Index < Count; Index++) {
+ mUartInfo[Index] = (UART_INFO *)AllocateZeroPool (sizeof (UART_INFO));
+ }
+
+ Index = 0;
+ GuidHob = GetFirstGuidHob (&gUniversalPayloadSerialPortInfoGuid);
+ while (GuidHob != NULL) {
+ SerialPortInfo = (UNIVERSAL_PAYLOAD_SERIAL_PORT_INFO *)GET_GUID_HOB_DATA (GuidHob);
+ SerialRegisterBase = SerialPortInfo->RegisterBase;
+ MmioEnable = SerialPortInfo->UseMmio;
+ BaudRate = SerialPortInfo->BaudRate;
+ RegisterStride = SerialPortInfo->RegisterStride;
+
+ mUartInfo[Index]->BaseAddress = SerialRegisterBase;
+ mUartInfo[Index]->UseMmio = MmioEnable;
+ mUartInfo[Index]->BaudRate = BaudRate;
+ mUartInfo[Index]->RegisterStride = RegisterStride;
+ Index++;
+
+ if (SerialRegisterBase == 0) {
+ return RETURN_DEVICE_ERROR;
+ }
+
+ Divisor = PcdGet32 (PcdSerialClockRate) / (BaudRate * 16);
+ if ((PcdGet32 (PcdSerialClockRate) % (BaudRate * 16)) >= BaudRate * 8) {
+ Divisor++;
+ }
+
+ //
+ // See if the serial port is already initialized
+ //
+ Initialized = TRUE;
+ if ((SerialPortReadRegister (SerialRegisterBase, R_UART_LCR, MmioEnable, RegisterStride) & 0x3F) != (PcdGet8 (PcdSerialLineControl) & 0x3F)) {
+ Initialized = FALSE;
+ }
+
+ SerialPortWriteRegister (SerialRegisterBase, R_UART_LCR, (UINT8)(SerialPortReadRegister (SerialRegisterBase, R_UART_LCR, MmioEnable, RegisterStride) | B_UART_LCR_DLAB), MmioEnable, RegisterStride);
+ CurrentDivisor = SerialPortReadRegister (SerialRegisterBase, R_UART_BAUD_HIGH, MmioEnable, RegisterStride) << 8;
+ CurrentDivisor |= (UINT32)SerialPortReadRegister (SerialRegisterBase, R_UART_BAUD_LOW, MmioEnable, RegisterStride);
+ SerialPortWriteRegister (SerialRegisterBase, R_UART_LCR, (UINT8)(SerialPortReadRegister (SerialRegisterBase, R_UART_LCR, MmioEnable, RegisterStride) & ~B_UART_LCR_DLAB), MmioEnable, RegisterStride);
+ if (CurrentDivisor != Divisor) {
+ Initialized = FALSE;
+ }
+
+ if (Initialized) {
+ GuidHob = GET_NEXT_HOB (GuidHob);
+ GuidHob = GetNextGuidHob (&gUniversalPayloadSerialPortInfoGuid, GuidHob);
+ continue;
+ }
+
+ //
+ // Configure baud rate
+ //
+ SerialPortWriteRegister (SerialRegisterBase, R_UART_LCR, B_UART_LCR_DLAB, MmioEnable, RegisterStride);
+ SerialPortWriteRegister (SerialRegisterBase, R_UART_BAUD_HIGH, (UINT8)(Divisor >> 8), MmioEnable, RegisterStride);
+ SerialPortWriteRegister (SerialRegisterBase, R_UART_BAUD_LOW, (UINT8)(Divisor & 0xff), MmioEnable, RegisterStride);
+
+ //
+ // Clear DLAB and configure Data Bits, Parity, and Stop Bits.
+ // Strip reserved bits from PcdSerialLineControl
+ //
+ SerialPortWriteRegister (SerialRegisterBase, R_UART_LCR, (UINT8)(PcdGet8 (PcdSerialLineControl) & 0x3F), MmioEnable, RegisterStride);
+
+ //
+ // Enable and reset FIFOs
+ // Strip reserved bits from PcdSerialFifoControl
+ //
+ SerialPortWriteRegister (SerialRegisterBase, R_UART_FCR, 0x00, MmioEnable, RegisterStride);
+ SerialPortWriteRegister (SerialRegisterBase, R_UART_FCR, (UINT8)(PcdGet8 (PcdSerialFifoControl) & (B_UART_FCR_FIFOE | B_UART_FCR_FIFO64)), MmioEnable, RegisterStride);
+
+ //
+ // Set FIFO Polled Mode by clearing IER after setting FCR
+ //
+ SerialPortWriteRegister (SerialRegisterBase, R_UART_IER, 0x00, MmioEnable, RegisterStride);
+
+ //
+ // Put Modem Control Register(MCR) into its reset state of 0x00.
+ //
+ SerialPortWriteRegister (SerialRegisterBase, R_UART_MCR, 0x00, MmioEnable, RegisterStride);
+
+ GuidHob = GET_NEXT_HOB (GuidHob);
+ GuidHob = GetNextGuidHob (&gUniversalPayloadSerialPortInfoGuid, GuidHob);
+ }
+
+ return RETURN_SUCCESS;
+}
+
+/**
+ Write data from buffer to serial device.
+
+ Writes NumberOfBytes data bytes from Buffer to the serial device.
+ The number of bytes actually written to the serial device is returned.
+ If the return value is less than NumberOfBytes, then the write operation failed.
+
+ If Buffer is NULL, then return 0.
+
+ If NumberOfBytes is zero, then return 0.
+
+ @param Buffer Pointer to the data buffer to be written.
+ @param NumberOfBytes Number of bytes to written to the serial device.
+
+ @retval 0 NumberOfBytes is 0.
+ @retval >0 The number of bytes written to the serial device.
+ If this value is less than NumberOfBytes, then the write operation failed.
+
+**/
+UINTN
+EFIAPI
+SerialPortWrite (
+ IN UINT8 *Buffer,
+ IN UINTN NumberOfBytes
+ )
+{
+ UINTN BaseAddress;
+ BOOLEAN UseMmio;
+ UINTN BytesLeft;
+ UINTN Index;
+ UINTN FifoSize;
+ UINT8 *DataBuffer;
+ UINT8 Count;
+ UINT8 Stride;
+
+ if (Buffer == NULL || NumberOfBytes == 0) {
+ return 0;
+ }
+
+ //
+ // Compute the maximum size of the Tx FIFO
+ //
+ FifoSize = 1;
+ if ((PcdGet8 (PcdSerialFifoControl) & B_UART_FCR_FIFOE) != 0) {
+ if ((PcdGet8 (PcdSerialFifoControl) & B_UART_FCR_FIFO64) == 0) {
+ FifoSize = 16;
+ } else {
+ FifoSize = PcdGet32 (PcdSerialExtendedTxFifoSize);
+ }
+ }
+
+ Count = 0;
+ while (Count < mUartCount) {
+ BaseAddress = mUartInfo[Count]->BaseAddress;
+ UseMmio = mUartInfo[Count]->UseMmio;
+ Stride = mUartInfo[Count]->RegisterStride;
+
+ DataBuffer = Buffer;
+ BytesLeft = NumberOfBytes;
+
+ while (BytesLeft != 0) {
+ //
+ // Fill the entire Tx FIFO
+ //
+ for (Index = 0; Index < FifoSize && BytesLeft != 0; Index++, BytesLeft--, DataBuffer++) {
+ //
+ // Write byte to the transmit buffer.
+ //
+ SerialPortWriteRegister (BaseAddress, R_UART_TXBUF, *DataBuffer, UseMmio, Stride);
+ }
+ MicroSecondDelay (20);
+ }
+ Count++;
+ }
+
+ return NumberOfBytes;
+}
+
+/**
+ Reads data from a serial device into a buffer.
+
+ @param Buffer Pointer to the data buffer to store the data read from the serial device.
+ @param NumberOfBytes Number of bytes to read from the serial device.
+
+ @retval 0 NumberOfBytes is 0.
+ @retval >0 The number of bytes read from the serial device.
+ If this value is less than NumberOfBytes, then the read operation failed.
+
+**/
+UINTN
+EFIAPI
+SerialPortRead (
+ OUT UINT8 *Buffer,
+ IN UINTN NumberOfBytes
+ )
+{
+ UINTN BaseAddress;
+ BOOLEAN UseMmio;
+ UINT8 *DataBuffer;
+ UINTN BytesLeft;
+ UINTN Result;
+ UINT8 Mcr;
+ UINT8 Count;
+ UINT8 Stride;
+
+ if (Buffer == NULL) {
+ return 0;
+ }
+
+ Count = 0;
+ while (Count < mUartCount) {
+ BaseAddress = mUartInfo[Count]->BaseAddress;
+ UseMmio = mUartInfo[Count]->UseMmio;
+ Stride = mUartInfo[Count]->RegisterStride;
+
+ DataBuffer = Buffer;
+ BytesLeft = NumberOfBytes;
+
+ if (BaseAddress == 0) {
+ return 0;
+ }
+
+ Mcr = (UINT8)(SerialPortReadRegister (BaseAddress, R_UART_MCR, UseMmio, Stride) & ~B_UART_MCR_RTS);
+
+ for (Result = 0; BytesLeft-- != 0; Result++, DataBuffer++) {
+ //
+ // Wait for the serial port to have some data.
+ //
+ while ((SerialPortReadRegister (BaseAddress, R_UART_LSR, UseMmio, Stride) & B_UART_LSR_RXRDY) == 0) {
+ if (PcdGetBool (PcdSerialUseHardwareFlowControl)) {
+ //
+ // Set RTS to let the peer send some data
+ //
+ SerialPortWriteRegister (BaseAddress, R_UART_MCR, (UINT8)(Mcr | B_UART_MCR_RTS), UseMmio, Stride);
+ }
+ }
+
+ if (PcdGetBool (PcdSerialUseHardwareFlowControl)) {
+ //
+ // Clear RTS to prevent peer from sending data
+ //
+ SerialPortWriteRegister (BaseAddress, R_UART_MCR, Mcr, UseMmio, Stride);
+ }
+
+ //
+ // Read byte from the receive buffer.
+ //
+ *DataBuffer = SerialPortReadRegister (BaseAddress, R_UART_RXBUF, UseMmio, Stride);
+ }
+ Count++;
+ }
+
+ return Result;
+}
+
+/**
+ Polls a serial device to see if there is any data waiting to be read.
+
+ Polls a serial device to see if there is any data waiting to be read.
+ If there is data waiting to be read from the serial device, then TRUE is returned.
+ If there is no data waiting to be read from the serial device, then FALSE is returned.
+
+ @retval TRUE Data is waiting to be read from the serial device.
+ @retval FALSE There is no data waiting to be read from the serial device.
+
+**/
+BOOLEAN
+EFIAPI
+SerialPortPoll (
+ VOID
+ )
+{
+ UINTN BaseAddress;
+ BOOLEAN UseMmio;
+ UINT8 Stride;
+ UINT8 Count;
+
+ Count = 0;
+ while (Count < mUartCount) {
+ BaseAddress = mUartInfo[Count]->BaseAddress;
+ UseMmio = mUartInfo[Count]->UseMmio;
+ Stride = mUartInfo[Count]->RegisterStride;
+
+ if (BaseAddress == 0) {
+ return FALSE;
+ }
+
+ //
+ // Read the serial port status
+ //
+ if ((SerialPortReadRegister (BaseAddress, R_UART_LSR, UseMmio, Stride) & B_UART_LSR_RXRDY) != 0) {
+ if (PcdGetBool (PcdSerialUseHardwareFlowControl)) {
+ //
+ // Clear RTS to prevent peer from sending data
+ //
+ SerialPortWriteRegister (BaseAddress, R_UART_MCR, (UINT8)(SerialPortReadRegister (BaseAddress, R_UART_MCR, UseMmio, Stride) & ~B_UART_MCR_RTS), UseMmio, Stride);
+ }
+ return TRUE;
+ }
+
+ if (PcdGetBool (PcdSerialUseHardwareFlowControl)) {
+ //
+ // Set RTS to let the peer send some data
+ //
+ SerialPortWriteRegister (BaseAddress, R_UART_MCR, (UINT8)(SerialPortReadRegister (BaseAddress, R_UART_MCR, UseMmio, Stride) | B_UART_MCR_RTS), UseMmio, Stride);
+ }
+ Count++;
+ }
+ return FALSE;
+}
+
+/**
+ Sets the control bits on a serial device.
+
+ @param Control Sets the bits of Control that are settable.
+
+ @retval RETURN_SUCCESS The new control bits were set on the serial device.
+ @retval RETURN_UNSUPPORTED The serial device does not support this operation.
+ @retval RETURN_DEVICE_ERROR The serial device is not functioning correctly.
+
+**/
+RETURN_STATUS
+EFIAPI
+SerialPortSetControl (
+ IN UINT32 Control
+ )
+{
+ UINTN BaseAddress;
+ BOOLEAN UseMmio;
+ UINT8 Mcr;
+ UINT8 Count;
+ UINT8 Stride;
+
+ Count = 0;
+ while (Count < mUartCount) {
+ BaseAddress = mUartInfo[Count]->BaseAddress;
+ UseMmio = mUartInfo[Count]->UseMmio;
+ Stride = mUartInfo[Count]->RegisterStride;
+
+ if (BaseAddress == 0) {
+ return RETURN_UNSUPPORTED;
+ }
+
+ //
+ // First determine the parameter is invalid.
+ //
+ if ((Control & (~(EFI_SERIAL_REQUEST_TO_SEND | EFI_SERIAL_DATA_TERMINAL_READY |
+ EFI_SERIAL_HARDWARE_FLOW_CONTROL_ENABLE))) != 0)
+ {
+ return RETURN_UNSUPPORTED;
+ }
+
+ //
+ // Read the Modem Control Register.
+ //
+ Mcr = SerialPortReadRegister (BaseAddress, R_UART_MCR, UseMmio, Stride);
+ Mcr &= (~(B_UART_MCR_DTRC | B_UART_MCR_RTS));
+
+ if ((Control & EFI_SERIAL_DATA_TERMINAL_READY) == EFI_SERIAL_DATA_TERMINAL_READY) {
+ Mcr |= B_UART_MCR_DTRC;
+ }
+
+ if ((Control & EFI_SERIAL_REQUEST_TO_SEND) == EFI_SERIAL_REQUEST_TO_SEND) {
+ Mcr |= B_UART_MCR_RTS;
+ }
+
+ //
+ // Write the Modem Control Register.
+ //
+ SerialPortWriteRegister (BaseAddress, R_UART_MCR, Mcr, UseMmio, Stride);
+ Count++;
+ }
+
+ return RETURN_SUCCESS;
+}
+
+/**
+ Retrieve the status of the control bits on a serial device.
+
+ @param Control A pointer to return the current control signals from the serial device.
+
+ @retval RETURN_SUCCESS The control bits were read from the serial device.
+ @retval RETURN_UNSUPPORTED The serial device does not support this operation.
+ @retval RETURN_DEVICE_ERROR The serial device is not functioning correctly.
+
+**/
+RETURN_STATUS
+EFIAPI
+SerialPortGetControl (
+ OUT UINT32 *Control
+ )
+{
+ UINTN BaseAddress;
+ BOOLEAN UseMmio;
+ UINT8 Msr;
+ UINT8 Mcr;
+ UINT8 Lsr;
+ UINT8 Count;
+ UINT8 Stride;
+
+ Count = 0;
+ while (Count < mUartCount) {
+ BaseAddress = mUartInfo[Count]->BaseAddress;
+ UseMmio = mUartInfo[Count]->UseMmio;
+ Stride = mUartInfo[Count]->RegisterStride;
+
+ if (BaseAddress == 0) {
+ return RETURN_UNSUPPORTED;
+ }
+
+ *Control = 0;
+
+ //
+ // Read the Modem Status Register.
+ //
+ Msr = SerialPortReadRegister (BaseAddress, R_UART_MSR, UseMmio, Stride);
+
+ if ((Msr & B_UART_MSR_CTS) == B_UART_MSR_CTS) {
+ *Control |= EFI_SERIAL_CLEAR_TO_SEND;
+ }
+
+ if ((Msr & B_UART_MSR_DSR) == B_UART_MSR_DSR) {
+ *Control |= EFI_SERIAL_DATA_SET_READY;
+ }
+
+ if ((Msr & B_UART_MSR_RI) == B_UART_MSR_RI) {
+ *Control |= EFI_SERIAL_RING_INDICATE;
+ }
+
+ if ((Msr & B_UART_MSR_DCD) == B_UART_MSR_DCD) {
+ *Control |= EFI_SERIAL_CARRIER_DETECT;
+ }
+
+ //
+ // Read the Modem Control Register.
+ //
+ Mcr = SerialPortReadRegister (BaseAddress, R_UART_MCR, UseMmio, Stride);
+
+ if ((Mcr & B_UART_MCR_DTRC) == B_UART_MCR_DTRC) {
+ *Control |= EFI_SERIAL_DATA_TERMINAL_READY;
+ }
+
+ if ((Mcr & B_UART_MCR_RTS) == B_UART_MCR_RTS) {
+ *Control |= EFI_SERIAL_REQUEST_TO_SEND;
+ }
+
+ if (PcdGetBool (PcdSerialUseHardwareFlowControl)) {
+ *Control |= EFI_SERIAL_HARDWARE_FLOW_CONTROL_ENABLE;
+ }
+
+ //
+ // Read the Line Status Register.
+ //
+ Lsr = SerialPortReadRegister (BaseAddress, R_UART_LSR, UseMmio, Stride);
+
+ if ((Lsr & (B_UART_LSR_TEMT | B_UART_LSR_TXRDY)) == (B_UART_LSR_TEMT | B_UART_LSR_TXRDY)) {
+ *Control |= EFI_SERIAL_OUTPUT_BUFFER_EMPTY;
+ }
+
+ if ((Lsr & B_UART_LSR_RXRDY) == 0) {
+ *Control |= EFI_SERIAL_INPUT_BUFFER_EMPTY;
+ }
+ Count++;
+ }
+
+ return RETURN_SUCCESS;
+}
+
+/**
+ Sets the baud rate, receive FIFO depth, transmit/receice time out, parity,
+ data bits, and stop bits on a serial device.
+
+ @param BaudRate The requested baud rate. A BaudRate value of 0 will use the
+ device's default interface speed.
+ On output, the value actually set.
+ @param ReveiveFifoDepth The requested depth of the FIFO on the receive side of the
+ serial interface. A ReceiveFifoDepth value of 0 will use
+ the device's default FIFO depth.
+ On output, the value actually set.
+ @param Timeout The requested time out for a single character in microseconds.
+ This timeout applies to both the transmit and receive side of the
+ interface. A Timeout value of 0 will use the device's default time
+ out value.
+ On output, the value actually set.
+ @param Parity The type of parity to use on this serial device. A Parity value of
+ DefaultParity will use the device's default parity value.
+ On output, the value actually set.
+ @param DataBits The number of data bits to use on the serial device. A DataBits
+ vaule of 0 will use the device's default data bit setting.
+ On output, the value actually set.
+ @param StopBits The number of stop bits to use on this serial device. A StopBits
+ value of DefaultStopBits will use the device's default number of
+ stop bits.
+ On output, the value actually set.
+
+ @retval RETURN_SUCCESS The new attributes were set on the serial device.
+ @retval RETURN_UNSUPPORTED The serial device does not support this operation.
+ @retval RETURN_INVALID_PARAMETER One or more of the attributes has an unsupported value.
+ @retval RETURN_DEVICE_ERROR The serial device is not functioning correctly.
+
+**/
+RETURN_STATUS
+EFIAPI
+SerialPortSetAttributes (
+ IN OUT UINT64 *BaudRate,
+ IN OUT UINT32 *ReceiveFifoDepth,
+ IN OUT UINT32 *Timeout,
+ IN OUT EFI_PARITY_TYPE *Parity,
+ IN OUT UINT8 *DataBits,
+ IN OUT EFI_STOP_BITS_TYPE *StopBits
+ )
+{
+ UINTN BaseAddress;
+ BOOLEAN UseMmio;
+ UINT32 SerialBaudRate;
+ UINTN Divisor;
+ UINT8 Lcr;
+ UINT8 LcrData;
+ UINT8 LcrParity;
+ UINT8 LcrStop;
+ UINT8 Count;
+ UINT8 Stride;
+
+ Count = 0;
+ while (Count < mUartCount) {
+ BaseAddress = mUartInfo[Count]->BaseAddress;
+ UseMmio = mUartInfo[Count]->UseMmio;
+ Stride = mUartInfo[Count]->RegisterStride;
+
+ if (BaseAddress == 0) {
+ return RETURN_UNSUPPORTED;
+ }
+
+ //
+ // Check for default settings and fill in actual values.
+ //
+ if (*BaudRate == 0) {
+ *BaudRate = mUartInfo[Count]->BaudRate;
+ }
+
+ SerialBaudRate = (UINT32)*BaudRate;
+
+ if (*DataBits == 0) {
+ LcrData = (UINT8)(PcdGet8 (PcdSerialLineControl) & 0x3);
+ *DataBits = LcrData + 5;
+ } else {
+ if ((*DataBits < 5) || (*DataBits > 8)) {
+ return RETURN_INVALID_PARAMETER;
+ }
+
+ //
+ // Map 5..8 to 0..3
+ //
+ LcrData = (UINT8)(*DataBits - (UINT8)5);
+ }
+
+ if (*Parity == DefaultParity) {
+ LcrParity = (UINT8)((PcdGet8 (PcdSerialLineControl) >> 3) & 0x7);
+ switch (LcrParity) {
+ case 0:
+ *Parity = NoParity;
+ break;
+
+ case 3:
+ *Parity = EvenParity;
+ break;
+
+ case 1:
+ *Parity = OddParity;
+ break;
+
+ case 7:
+ *Parity = SpaceParity;
+ break;
+
+ case 5:
+ *Parity = MarkParity;
+ break;
+
+ default:
+ break;
+ }
+ } else {
+ switch (*Parity) {
+ case NoParity:
+ LcrParity = 0;
+ break;
+
+ case EvenParity:
+ LcrParity = 3;
+ break;
+
+ case OddParity:
+ LcrParity = 1;
+ break;
+
+ case SpaceParity:
+ LcrParity = 7;
+ break;
+
+ case MarkParity:
+ LcrParity = 5;
+ break;
+
+ default:
+ return RETURN_INVALID_PARAMETER;
+ }
+ }
+
+ if (*StopBits == DefaultStopBits) {
+ LcrStop = (UINT8)((PcdGet8 (PcdSerialLineControl) >> 2) & 0x1);
+ switch (LcrStop) {
+ case 0:
+ *StopBits = OneStopBit;
+ break;
+
+ case 1:
+ if (*DataBits == 5) {
+ *StopBits = OneFiveStopBits;
+ } else {
+ *StopBits = TwoStopBits;
+ }
+
+ break;
+
+ default:
+ break;
+ }
+ } else {
+ switch (*StopBits) {
+ case OneStopBit:
+ LcrStop = 0;
+ break;
+
+ case OneFiveStopBits:
+ case TwoStopBits:
+ LcrStop = 1;
+ break;
+
+ default:
+ return RETURN_INVALID_PARAMETER;
+ }
+ }
+
+ //
+ // Calculate divisor for baud generator
+ // Ref_Clk_Rate / Baud_Rate / 16
+ //
+ Divisor = PcdGet32 (PcdSerialClockRate) / (SerialBaudRate * 16);
+ if ((PcdGet32 (PcdSerialClockRate) % (SerialBaudRate * 16)) >= SerialBaudRate * 8) {
+ Divisor++;
+ }
+
+ //
+ // Configure baud rate
+ //
+ SerialPortWriteRegister (BaseAddress, R_UART_LCR, B_UART_LCR_DLAB, UseMmio, Stride);
+ SerialPortWriteRegister (BaseAddress, R_UART_BAUD_HIGH, (UINT8)(Divisor >> 8), UseMmio, Stride);
+ SerialPortWriteRegister (BaseAddress, R_UART_BAUD_LOW, (UINT8)(Divisor & 0xff), UseMmio, Stride);
+
+ //
+ // Clear DLAB and configure Data Bits, Parity, and Stop Bits.
+ // Strip reserved bits from line control value
+ //
+ Lcr = (UINT8)((LcrParity << 3) | (LcrStop << 2) | LcrData);
+ SerialPortWriteRegister (BaseAddress, R_UART_LCR, (UINT8)(Lcr & 0x3F), UseMmio, Stride);
+ Count++;
+ }
+
+ return RETURN_SUCCESS;
+}
diff --git a/UefiPayloadPkg/Library/BaseSerialPortLibHob/BaseSerialPortLibHob.inf b/UefiPayloadPkg/Library/BaseSerialPortLibHob/BaseSerialPortLibHob.inf
new file mode 100644
index 0000000000..1dbe107dbd
--- /dev/null
+++ b/UefiPayloadPkg/Library/BaseSerialPortLibHob/BaseSerialPortLibHob.inf
@@ -0,0 +1,40 @@
+## @file
+# SerialPortLib instance for UART information retrieved from bootloader.
+#
+# Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
+#
+# SPDX-License-Identifier: BSD-2-Clause-Patent
+#
+##
+
+[Defines]
+ INF_VERSION = 0x00010005
+ BASE_NAME = BaseSerialPortLibHob
+ FILE_GUID = d8d22930-e8ec-469f-8184-5a069149b2ff
+ MODULE_TYPE = BASE
+ VERSION_STRING = 1.0
+ LIBRARY_CLASS = SerialPortLib
+
+[Packages]
+ MdePkg/MdePkg.dec
+ MdeModulePkg/MdeModulePkg.dec
+
+[LibraryClasses]
+ PcdLib
+ IoLib
+ HobLib
+ TimerLib
+ MemoryAllocationLib
+
+[Sources]
+ BaseSerialPortLibHob.c
+
+[Pcd]
+ gEfiMdeModulePkgTokenSpaceGuid.PcdSerialLineControl
+ gEfiMdeModulePkgTokenSpaceGuid.PcdSerialFifoControl
+ gEfiMdeModulePkgTokenSpaceGuid.PcdSerialClockRate
+ gEfiMdeModulePkgTokenSpaceGuid.PcdSerialExtendedTxFifoSize
+ gEfiMdeModulePkgTokenSpaceGuid.PcdSerialUseHardwareFlowControl
+
+[Guids]
+ gUniversalPayloadSerialPortInfoGuid
--
2.30.2.windows.1
^ permalink raw reply related [flat|nested] 3+ messages in thread
* [PATCH v3 2/2] UefiPayloadPkg: Allow DxeMain.inf to consume the new SerialPortLib
2022-07-21 9:14 [PATCH v3 1/2] UefiPayloadPkg: Implement a new SerialPortLib instance kavya
@ 2022-07-21 9:14 ` kavya
2022-07-21 9:18 ` [PATCH v3 1/2] UefiPayloadPkg: Implement a new SerialPortLib instance Ni, Ray
1 sibling, 0 replies; 3+ messages in thread
From: kavya @ 2022-07-21 9:14 UTC (permalink / raw)
To: devel; +Cc: Kavya, Guo Dong, Ray Ni, Sean Rhodes, Gua Guo
Let DxeMain.inf consume new SerialPortLib to support multiple
channel debug message on early DXE.
Cc: Guo Dong <guo.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Sean Rhodes <sean@starlabs.systems>
Cc: Gua Guo <gua.guo@intel.com>
Signed-off-by: Kavya <k.kavyax.sravanthi@intel.com>
---
UefiPayloadPkg/UefiPayloadPkg.dsc | 2 ++
1 file changed, 2 insertions(+)
diff --git a/UefiPayloadPkg/UefiPayloadPkg.dsc b/UefiPayloadPkg/UefiPayloadPkg.dsc
index 5e947526b7..33eed40370 100644
--- a/UefiPayloadPkg/UefiPayloadPkg.dsc
+++ b/UefiPayloadPkg/UefiPayloadPkg.dsc
@@ -582,6 +582,8 @@
#
MdeModulePkg/Core/Dxe/DxeMain.inf {
<LibraryClasses>
+ DebugLib|MdePkg/Library/BaseDebugLibSerialPort/BaseDebugLibSerialPort.inf
+ SerialPortLib|UefiPayloadPkg/Library/BaseSerialPortLibHob/BaseSerialPortLibHob.inf
NULL|MdeModulePkg/Library/LzmaCustomDecompressLib/LzmaCustomDecompressLib.inf
}
--
2.30.2.windows.1
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH v3 1/2] UefiPayloadPkg: Implement a new SerialPortLib instance
2022-07-21 9:14 [PATCH v3 1/2] UefiPayloadPkg: Implement a new SerialPortLib instance kavya
2022-07-21 9:14 ` [PATCH v3 2/2] UefiPayloadPkg: Allow DxeMain.inf to consume the new SerialPortLib kavya
@ 2022-07-21 9:18 ` Ni, Ray
1 sibling, 0 replies; 3+ messages in thread
From: Ni, Ray @ 2022-07-21 9:18 UTC (permalink / raw)
To: Sravanthi, K KavyaX, devel@edk2.groups.io
Cc: Dong, Guo, Rhodes, Sean, Guo, Gua
Please try to not use AllocatePool in this library because in early part
of DxeMain, the memory service may not be available.
You could use a C array with maximum maybe 16 elements.
Then the SerialPortLib may only support up to 16 serial ports.
But I think that should be enough.
Thanks,
Ray
> -----Original Message-----
> From: Sravanthi, K KavyaX <k.kavyax.sravanthi@intel.com>
> Sent: Thursday, July 21, 2022 5:14 PM
> To: devel@edk2.groups.io
> Cc: Sravanthi, K KavyaX <k.kavyax.sravanthi@intel.com>; Dong, Guo
> <guo.dong@intel.com>; Ni, Ray <ray.ni@intel.com>; Rhodes, Sean
> <sean@starlabs.systems>; Guo, Gua <gua.guo@intel.com>
> Subject: [PATCH v3 1/2] UefiPayloadPkg: Implement a new SerialPortLib
> instance
>
> Add new Serial port library instance that consumes the HOB defined
> in MdeModulePkg/Include/UniversalPayload/SerialPortInfo.h to support
> multiple UART's.
>
> Cc: Guo Dong <guo.dong@intel.com>
> Cc: Ray Ni <ray.ni@intel.com>
> Cc: Sean Rhodes <sean@starlabs.systems>
> Cc: Gua Guo <gua.guo@intel.com>
> Signed-off-by: Kavya <k.kavyax.sravanthi@intel.com>
> ---
> UefiPayloadPkg/Library/BaseSerialPortLibHob/BaseSerialPortLibHob.c | 814
> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
> ++
> UefiPayloadPkg/Library/BaseSerialPortLibHob/BaseSerialPortLibHob.inf | 40
> ++++++++++++++++++++++++++++++++++++++++
> 2 files changed, 854 insertions(+)
>
> diff --git
> a/UefiPayloadPkg/Library/BaseSerialPortLibHob/BaseSerialPortLibHob.c
> b/UefiPayloadPkg/Library/BaseSerialPortLibHob/BaseSerialPortLibHob.c
> new file mode 100644
> index 0000000000..13eddf0934
> --- /dev/null
> +++ b/UefiPayloadPkg/Library/BaseSerialPortLibHob/BaseSerialPortLibHob.c
> @@ -0,0 +1,814 @@
> +/** @file
> + UART Serial Port library functions.
> +
> + Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
> + SPDX-License-Identifier: BSD-2-Clause-Patent
> +
> +**/
> +#include <PiDxe.h>
> +#include <Base.h>
> +#include <Library/PcdLib.h>
> +#include <Library/IoLib.h>
> +#include <Library/BaseLib.h>
> +#include <Library/HobLib.h>
> +#include <Library/TimerLib.h>
> +#include <Library/DebugLib.h>
> +#include <Library/MemoryAllocationLib.h>
> +#include <Protocol/SerialIo.h>
> +#include <UniversalPayload/SerialPortInfo.h>
> +
> +//
> +// 16550 UART register offsets and bitfields
> +//
> +#define R_UART_RXBUF 0 // LCR_DLAB = 0
> +#define R_UART_TXBUF 0 // LCR_DLAB = 0
> +#define R_UART_BAUD_LOW 0 // LCR_DLAB = 1
> +#define R_UART_BAUD_HIGH 1 // LCR_DLAB = 1
> +#define R_UART_IER 1 // LCR_DLAB = 0
> +#define R_UART_FCR 2
> +#define B_UART_FCR_FIFOE BIT0
> +#define B_UART_FCR_FIFO64 BIT5
> +#define R_UART_LCR 3
> +#define B_UART_LCR_DLAB BIT7
> +#define R_UART_MCR 4
> +#define B_UART_MCR_DTRC BIT0
> +#define B_UART_MCR_RTS BIT1
> +#define R_UART_LSR 5
> +#define B_UART_LSR_RXRDY BIT0
> +#define B_UART_LSR_TXRDY BIT5
> +#define B_UART_LSR_TEMT BIT6
> +#define R_UART_MSR 6
> +#define B_UART_MSR_CTS BIT4
> +#define B_UART_MSR_DSR BIT5
> +#define B_UART_MSR_RI BIT6
> +#define B_UART_MSR_DCD BIT7
> +
> +typedef struct {
> + UINTN BaseAddress;
> + BOOLEAN UseMmio;
> + UINT32 BaudRate;
> + UINT8 RegisterStride;
> +} UART_INFO;
> +
> +UART_INFO **mUartInfo;
> +UINT8 mUartCount;
> +
> +/**
> + Reads an 8-bit register. If UseMmio is TRUE, then the value is read from
> + MMIO space. If UseMmio is FALSE, then the value is read from I/O space.
> The
> + parameter Offset is added to the base address of the register.
> +
> + @param Base The base address register of UART device.
> + @param Offset The offset of the register to read.
> + @param UseMmio Check if value has to be read from MMIO space or
> IO space.
> + @param RegisterStride Number of bytes between registers in serial
> device.
> +
> + @return The value read from the register.
> +
> +**/
> +UINT8
> +SerialPortReadRegister (
> + UINTN Base,
> + UINTN Offset,
> + BOOLEAN UseMmio,
> + UINT8 RegisterStride
> + )
> +{
> + if (UseMmio) {
> + return MmioRead8 (Base + Offset * RegisterStride);
> + } else {
> + return IoRead8 (Base + Offset * RegisterStride);
> + }
> +}
> +
> +/**
> + Writes an 8-bit register.. If UseMmio is TRUE, then the value is written to
> + MMIO space. If UseMmio is FALSE, then the value is written to I/O space.
> The
> + parameter Offset is added to the base address of the registers.
> +
> + @param Base The base address register of UART device.
> + @param Offset The offset of the register to write.
> + @param Value Value to be written.
> + @param UseMmio Check if value has to be written to MMIO space or
> IO space.
> + @param RegisterStride Number of bytes between registers in serial
> device.
> +
> + @return The value written to the register.
> +
> +**/
> +UINT8
> +SerialPortWriteRegister (
> + UINTN Base,
> + UINTN Offset,
> + UINT8 Value,
> + BOOLEAN UseMmio,
> + UINT8 RegisterStride
> + )
> +{
> + if (UseMmio) {
> + return MmioWrite8 (Base + Offset * RegisterStride, Value);
> + } else {
> + return IoWrite8 (Base + Offset * RegisterStride, Value);
> + }
> +}
> +
> +/**
> + Initialize the serial device hardware.
> +
> + If no initialization is required, then return RETURN_SUCCESS.
> + If the serial device was successfully initialized, then return
> RETURN_SUCCESS.
> + If the serial device could not be initialized, then return
> RETURN_DEVICE_ERROR.
> +
> + @retval RETURN_SUCCESS The serial device was initialized.
> + @retval RETURN_DEVICE_ERROR The serial device could not be initialized.
> +
> +**/
> +RETURN_STATUS
> +EFIAPI
> +SerialPortInitialize (
> + VOID
> + )
> +{
> + UNIVERSAL_PAYLOAD_SERIAL_PORT_INFO *SerialPortInfo;
> + EFI_HOB_GUID_TYPE *GuidHob;
> + UINTN SerialRegisterBase;
> + UINT8 RegisterStride;
> + UINT32 Divisor;
> + UINT32 CurrentDivisor;
> + UINT32 BaudRate;
> + BOOLEAN Initialized;
> + BOOLEAN MmioEnable;
> + UINT8 Index;
> + UINT8 Count;
> +
> + Count = 0;
> +
> + GuidHob = GetFirstGuidHob (&gUniversalPayloadSerialPortInfoGuid);
> + while (GuidHob != NULL) {
> + Count++;
> + GuidHob = GET_NEXT_HOB (GuidHob);
> + GuidHob = GetNextGuidHob (&gUniversalPayloadSerialPortInfoGuid,
> GuidHob);
> + }
> +
> + mUartCount = Count;
> +
> + mUartInfo = (UART_INFO **)AllocateZeroPool (sizeof (UART_INFO *) *
> Count);
> + ASSERT (mUartInfo != NULL);
> +
> + for (Index = 0; Index < Count; Index++) {
> + mUartInfo[Index] = (UART_INFO *)AllocateZeroPool (sizeof
> (UART_INFO));
> + }
> +
> + Index = 0;
> + GuidHob = GetFirstGuidHob (&gUniversalPayloadSerialPortInfoGuid);
> + while (GuidHob != NULL) {
> + SerialPortInfo = (UNIVERSAL_PAYLOAD_SERIAL_PORT_INFO
> *)GET_GUID_HOB_DATA (GuidHob);
> + SerialRegisterBase = SerialPortInfo->RegisterBase;
> + MmioEnable = SerialPortInfo->UseMmio;
> + BaudRate = SerialPortInfo->BaudRate;
> + RegisterStride = SerialPortInfo->RegisterStride;
> +
> + mUartInfo[Index]->BaseAddress = SerialRegisterBase;
> + mUartInfo[Index]->UseMmio = MmioEnable;
> + mUartInfo[Index]->BaudRate = BaudRate;
> + mUartInfo[Index]->RegisterStride = RegisterStride;
> + Index++;
> +
> + if (SerialRegisterBase == 0) {
> + return RETURN_DEVICE_ERROR;
> + }
> +
> + Divisor = PcdGet32 (PcdSerialClockRate) / (BaudRate * 16);
> + if ((PcdGet32 (PcdSerialClockRate) % (BaudRate * 16)) >= BaudRate * 8) {
> + Divisor++;
> + }
> +
> + //
> + // See if the serial port is already initialized
> + //
> + Initialized = TRUE;
> + if ((SerialPortReadRegister (SerialRegisterBase, R_UART_LCR,
> MmioEnable, RegisterStride) & 0x3F) != (PcdGet8 (PcdSerialLineControl) &
> 0x3F)) {
> + Initialized = FALSE;
> + }
> +
> + SerialPortWriteRegister (SerialRegisterBase, R_UART_LCR,
> (UINT8)(SerialPortReadRegister (SerialRegisterBase, R_UART_LCR,
> MmioEnable, RegisterStride) | B_UART_LCR_DLAB), MmioEnable,
> RegisterStride);
> + CurrentDivisor = SerialPortReadRegister (SerialRegisterBase,
> R_UART_BAUD_HIGH, MmioEnable, RegisterStride) << 8;
> + CurrentDivisor |= (UINT32)SerialPortReadRegister (SerialRegisterBase,
> R_UART_BAUD_LOW, MmioEnable, RegisterStride);
> + SerialPortWriteRegister (SerialRegisterBase, R_UART_LCR,
> (UINT8)(SerialPortReadRegister (SerialRegisterBase, R_UART_LCR,
> MmioEnable, RegisterStride) & ~B_UART_LCR_DLAB), MmioEnable,
> RegisterStride);
> + if (CurrentDivisor != Divisor) {
> + Initialized = FALSE;
> + }
> +
> + if (Initialized) {
> + GuidHob = GET_NEXT_HOB (GuidHob);
> + GuidHob = GetNextGuidHob (&gUniversalPayloadSerialPortInfoGuid,
> GuidHob);
> + continue;
> + }
> +
> + //
> + // Configure baud rate
> + //
> + SerialPortWriteRegister (SerialRegisterBase, R_UART_LCR,
> B_UART_LCR_DLAB, MmioEnable, RegisterStride);
> + SerialPortWriteRegister (SerialRegisterBase, R_UART_BAUD_HIGH,
> (UINT8)(Divisor >> 8), MmioEnable, RegisterStride);
> + SerialPortWriteRegister (SerialRegisterBase, R_UART_BAUD_LOW,
> (UINT8)(Divisor & 0xff), MmioEnable, RegisterStride);
> +
> + //
> + // Clear DLAB and configure Data Bits, Parity, and Stop Bits.
> + // Strip reserved bits from PcdSerialLineControl
> + //
> + SerialPortWriteRegister (SerialRegisterBase, R_UART_LCR,
> (UINT8)(PcdGet8 (PcdSerialLineControl) & 0x3F), MmioEnable,
> RegisterStride);
> +
> + //
> + // Enable and reset FIFOs
> + // Strip reserved bits from PcdSerialFifoControl
> + //
> + SerialPortWriteRegister (SerialRegisterBase, R_UART_FCR, 0x00,
> MmioEnable, RegisterStride);
> + SerialPortWriteRegister (SerialRegisterBase, R_UART_FCR,
> (UINT8)(PcdGet8 (PcdSerialFifoControl) & (B_UART_FCR_FIFOE |
> B_UART_FCR_FIFO64)), MmioEnable, RegisterStride);
> +
> + //
> + // Set FIFO Polled Mode by clearing IER after setting FCR
> + //
> + SerialPortWriteRegister (SerialRegisterBase, R_UART_IER, 0x00,
> MmioEnable, RegisterStride);
> +
> + //
> + // Put Modem Control Register(MCR) into its reset state of 0x00.
> + //
> + SerialPortWriteRegister (SerialRegisterBase, R_UART_MCR, 0x00,
> MmioEnable, RegisterStride);
> +
> + GuidHob = GET_NEXT_HOB (GuidHob);
> + GuidHob = GetNextGuidHob (&gUniversalPayloadSerialPortInfoGuid,
> GuidHob);
> + }
> +
> + return RETURN_SUCCESS;
> +}
> +
> +/**
> + Write data from buffer to serial device.
> +
> + Writes NumberOfBytes data bytes from Buffer to the serial device.
> + The number of bytes actually written to the serial device is returned.
> + If the return value is less than NumberOfBytes, then the write operation
> failed.
> +
> + If Buffer is NULL, then return 0.
> +
> + If NumberOfBytes is zero, then return 0.
> +
> + @param Buffer Pointer to the data buffer to be written.
> + @param NumberOfBytes Number of bytes to written to the serial device.
> +
> + @retval 0 NumberOfBytes is 0.
> + @retval >0 The number of bytes written to the serial device.
> + If this value is less than NumberOfBytes, then the write
> operation failed.
> +
> +**/
> +UINTN
> +EFIAPI
> +SerialPortWrite (
> + IN UINT8 *Buffer,
> + IN UINTN NumberOfBytes
> + )
> +{
> + UINTN BaseAddress;
> + BOOLEAN UseMmio;
> + UINTN BytesLeft;
> + UINTN Index;
> + UINTN FifoSize;
> + UINT8 *DataBuffer;
> + UINT8 Count;
> + UINT8 Stride;
> +
> + if (Buffer == NULL || NumberOfBytes == 0) {
> + return 0;
> + }
> +
> + //
> + // Compute the maximum size of the Tx FIFO
> + //
> + FifoSize = 1;
> + if ((PcdGet8 (PcdSerialFifoControl) & B_UART_FCR_FIFOE) != 0) {
> + if ((PcdGet8 (PcdSerialFifoControl) & B_UART_FCR_FIFO64) == 0) {
> + FifoSize = 16;
> + } else {
> + FifoSize = PcdGet32 (PcdSerialExtendedTxFifoSize);
> + }
> + }
> +
> + Count = 0;
> + while (Count < mUartCount) {
> + BaseAddress = mUartInfo[Count]->BaseAddress;
> + UseMmio = mUartInfo[Count]->UseMmio;
> + Stride = mUartInfo[Count]->RegisterStride;
> +
> + DataBuffer = Buffer;
> + BytesLeft = NumberOfBytes;
> +
> + while (BytesLeft != 0) {
> + //
> + // Fill the entire Tx FIFO
> + //
> + for (Index = 0; Index < FifoSize && BytesLeft != 0; Index++, BytesLeft--,
> DataBuffer++) {
> + //
> + // Write byte to the transmit buffer.
> + //
> + SerialPortWriteRegister (BaseAddress, R_UART_TXBUF, *DataBuffer,
> UseMmio, Stride);
> + }
> + MicroSecondDelay (20);
> + }
> + Count++;
> + }
> +
> + return NumberOfBytes;
> +}
> +
> +/**
> + Reads data from a serial device into a buffer.
> +
> + @param Buffer Pointer to the data buffer to store the data read from
> the serial device.
> + @param NumberOfBytes Number of bytes to read from the serial device.
> +
> + @retval 0 NumberOfBytes is 0.
> + @retval >0 The number of bytes read from the serial device.
> + If this value is less than NumberOfBytes, then the read
> operation failed.
> +
> +**/
> +UINTN
> +EFIAPI
> +SerialPortRead (
> + OUT UINT8 *Buffer,
> + IN UINTN NumberOfBytes
> + )
> +{
> + UINTN BaseAddress;
> + BOOLEAN UseMmio;
> + UINT8 *DataBuffer;
> + UINTN BytesLeft;
> + UINTN Result;
> + UINT8 Mcr;
> + UINT8 Count;
> + UINT8 Stride;
> +
> + if (Buffer == NULL) {
> + return 0;
> + }
> +
> + Count = 0;
> + while (Count < mUartCount) {
> + BaseAddress = mUartInfo[Count]->BaseAddress;
> + UseMmio = mUartInfo[Count]->UseMmio;
> + Stride = mUartInfo[Count]->RegisterStride;
> +
> + DataBuffer = Buffer;
> + BytesLeft = NumberOfBytes;
> +
> + if (BaseAddress == 0) {
> + return 0;
> + }
> +
> + Mcr = (UINT8)(SerialPortReadRegister (BaseAddress, R_UART_MCR,
> UseMmio, Stride) & ~B_UART_MCR_RTS);
> +
> + for (Result = 0; BytesLeft-- != 0; Result++, DataBuffer++) {
> + //
> + // Wait for the serial port to have some data.
> + //
> + while ((SerialPortReadRegister (BaseAddress, R_UART_LSR, UseMmio,
> Stride) & B_UART_LSR_RXRDY) == 0) {
> + if (PcdGetBool (PcdSerialUseHardwareFlowControl)) {
> + //
> + // Set RTS to let the peer send some data
> + //
> + SerialPortWriteRegister (BaseAddress, R_UART_MCR, (UINT8)(Mcr |
> B_UART_MCR_RTS), UseMmio, Stride);
> + }
> + }
> +
> + if (PcdGetBool (PcdSerialUseHardwareFlowControl)) {
> + //
> + // Clear RTS to prevent peer from sending data
> + //
> + SerialPortWriteRegister (BaseAddress, R_UART_MCR, Mcr, UseMmio,
> Stride);
> + }
> +
> + //
> + // Read byte from the receive buffer.
> + //
> + *DataBuffer = SerialPortReadRegister (BaseAddress, R_UART_RXBUF,
> UseMmio, Stride);
> + }
> + Count++;
> + }
> +
> + return Result;
> +}
> +
> +/**
> + Polls a serial device to see if there is any data waiting to be read.
> +
> + Polls a serial device to see if there is any data waiting to be read.
> + If there is data waiting to be read from the serial device, then TRUE is
> returned.
> + If there is no data waiting to be read from the serial device, then FALSE is
> returned.
> +
> + @retval TRUE Data is waiting to be read from the serial device.
> + @retval FALSE There is no data waiting to be read from the serial
> device.
> +
> +**/
> +BOOLEAN
> +EFIAPI
> +SerialPortPoll (
> + VOID
> + )
> +{
> + UINTN BaseAddress;
> + BOOLEAN UseMmio;
> + UINT8 Stride;
> + UINT8 Count;
> +
> + Count = 0;
> + while (Count < mUartCount) {
> + BaseAddress = mUartInfo[Count]->BaseAddress;
> + UseMmio = mUartInfo[Count]->UseMmio;
> + Stride = mUartInfo[Count]->RegisterStride;
> +
> + if (BaseAddress == 0) {
> + return FALSE;
> + }
> +
> + //
> + // Read the serial port status
> + //
> + if ((SerialPortReadRegister (BaseAddress, R_UART_LSR, UseMmio, Stride)
> & B_UART_LSR_RXRDY) != 0) {
> + if (PcdGetBool (PcdSerialUseHardwareFlowControl)) {
> + //
> + // Clear RTS to prevent peer from sending data
> + //
> + SerialPortWriteRegister (BaseAddress, R_UART_MCR,
> (UINT8)(SerialPortReadRegister (BaseAddress, R_UART_MCR, UseMmio,
> Stride) & ~B_UART_MCR_RTS), UseMmio, Stride);
> + }
> + return TRUE;
> + }
> +
> + if (PcdGetBool (PcdSerialUseHardwareFlowControl)) {
> + //
> + // Set RTS to let the peer send some data
> + //
> + SerialPortWriteRegister (BaseAddress, R_UART_MCR,
> (UINT8)(SerialPortReadRegister (BaseAddress, R_UART_MCR, UseMmio,
> Stride) | B_UART_MCR_RTS), UseMmio, Stride);
> + }
> + Count++;
> + }
> + return FALSE;
> +}
> +
> +/**
> + Sets the control bits on a serial device.
> +
> + @param Control Sets the bits of Control that are settable.
> +
> + @retval RETURN_SUCCESS The new control bits were set on the serial
> device.
> + @retval RETURN_UNSUPPORTED The serial device does not support this
> operation.
> + @retval RETURN_DEVICE_ERROR The serial device is not functioning
> correctly.
> +
> +**/
> +RETURN_STATUS
> +EFIAPI
> +SerialPortSetControl (
> + IN UINT32 Control
> + )
> +{
> + UINTN BaseAddress;
> + BOOLEAN UseMmio;
> + UINT8 Mcr;
> + UINT8 Count;
> + UINT8 Stride;
> +
> + Count = 0;
> + while (Count < mUartCount) {
> + BaseAddress = mUartInfo[Count]->BaseAddress;
> + UseMmio = mUartInfo[Count]->UseMmio;
> + Stride = mUartInfo[Count]->RegisterStride;
> +
> + if (BaseAddress == 0) {
> + return RETURN_UNSUPPORTED;
> + }
> +
> + //
> + // First determine the parameter is invalid.
> + //
> + if ((Control & (~(EFI_SERIAL_REQUEST_TO_SEND |
> EFI_SERIAL_DATA_TERMINAL_READY |
> + EFI_SERIAL_HARDWARE_FLOW_CONTROL_ENABLE))) != 0)
> + {
> + return RETURN_UNSUPPORTED;
> + }
> +
> + //
> + // Read the Modem Control Register.
> + //
> + Mcr = SerialPortReadRegister (BaseAddress, R_UART_MCR, UseMmio,
> Stride);
> + Mcr &= (~(B_UART_MCR_DTRC | B_UART_MCR_RTS));
> +
> + if ((Control & EFI_SERIAL_DATA_TERMINAL_READY) ==
> EFI_SERIAL_DATA_TERMINAL_READY) {
> + Mcr |= B_UART_MCR_DTRC;
> + }
> +
> + if ((Control & EFI_SERIAL_REQUEST_TO_SEND) ==
> EFI_SERIAL_REQUEST_TO_SEND) {
> + Mcr |= B_UART_MCR_RTS;
> + }
> +
> + //
> + // Write the Modem Control Register.
> + //
> + SerialPortWriteRegister (BaseAddress, R_UART_MCR, Mcr, UseMmio,
> Stride);
> + Count++;
> + }
> +
> + return RETURN_SUCCESS;
> +}
> +
> +/**
> + Retrieve the status of the control bits on a serial device.
> +
> + @param Control A pointer to return the current control signals
> from the serial device.
> +
> + @retval RETURN_SUCCESS The control bits were read from the serial
> device.
> + @retval RETURN_UNSUPPORTED The serial device does not support this
> operation.
> + @retval RETURN_DEVICE_ERROR The serial device is not functioning
> correctly.
> +
> +**/
> +RETURN_STATUS
> +EFIAPI
> +SerialPortGetControl (
> + OUT UINT32 *Control
> + )
> +{
> + UINTN BaseAddress;
> + BOOLEAN UseMmio;
> + UINT8 Msr;
> + UINT8 Mcr;
> + UINT8 Lsr;
> + UINT8 Count;
> + UINT8 Stride;
> +
> + Count = 0;
> + while (Count < mUartCount) {
> + BaseAddress = mUartInfo[Count]->BaseAddress;
> + UseMmio = mUartInfo[Count]->UseMmio;
> + Stride = mUartInfo[Count]->RegisterStride;
> +
> + if (BaseAddress == 0) {
> + return RETURN_UNSUPPORTED;
> + }
> +
> + *Control = 0;
> +
> + //
> + // Read the Modem Status Register.
> + //
> + Msr = SerialPortReadRegister (BaseAddress, R_UART_MSR, UseMmio,
> Stride);
> +
> + if ((Msr & B_UART_MSR_CTS) == B_UART_MSR_CTS) {
> + *Control |= EFI_SERIAL_CLEAR_TO_SEND;
> + }
> +
> + if ((Msr & B_UART_MSR_DSR) == B_UART_MSR_DSR) {
> + *Control |= EFI_SERIAL_DATA_SET_READY;
> + }
> +
> + if ((Msr & B_UART_MSR_RI) == B_UART_MSR_RI) {
> + *Control |= EFI_SERIAL_RING_INDICATE;
> + }
> +
> + if ((Msr & B_UART_MSR_DCD) == B_UART_MSR_DCD) {
> + *Control |= EFI_SERIAL_CARRIER_DETECT;
> + }
> +
> + //
> + // Read the Modem Control Register.
> + //
> + Mcr = SerialPortReadRegister (BaseAddress, R_UART_MCR, UseMmio,
> Stride);
> +
> + if ((Mcr & B_UART_MCR_DTRC) == B_UART_MCR_DTRC) {
> + *Control |= EFI_SERIAL_DATA_TERMINAL_READY;
> + }
> +
> + if ((Mcr & B_UART_MCR_RTS) == B_UART_MCR_RTS) {
> + *Control |= EFI_SERIAL_REQUEST_TO_SEND;
> + }
> +
> + if (PcdGetBool (PcdSerialUseHardwareFlowControl)) {
> + *Control |= EFI_SERIAL_HARDWARE_FLOW_CONTROL_ENABLE;
> + }
> +
> + //
> + // Read the Line Status Register.
> + //
> + Lsr = SerialPortReadRegister (BaseAddress, R_UART_LSR, UseMmio,
> Stride);
> +
> + if ((Lsr & (B_UART_LSR_TEMT | B_UART_LSR_TXRDY)) ==
> (B_UART_LSR_TEMT | B_UART_LSR_TXRDY)) {
> + *Control |= EFI_SERIAL_OUTPUT_BUFFER_EMPTY;
> + }
> +
> + if ((Lsr & B_UART_LSR_RXRDY) == 0) {
> + *Control |= EFI_SERIAL_INPUT_BUFFER_EMPTY;
> + }
> + Count++;
> + }
> +
> + return RETURN_SUCCESS;
> +}
> +
> +/**
> + Sets the baud rate, receive FIFO depth, transmit/receice time out, parity,
> + data bits, and stop bits on a serial device.
> +
> + @param BaudRate The requested baud rate. A BaudRate value of 0
> will use the
> + device's default interface speed.
> + On output, the value actually set.
> + @param ReveiveFifoDepth The requested depth of the FIFO on the
> receive side of the
> + serial interface. A ReceiveFifoDepth value of 0 will use
> + the device's default FIFO depth.
> + On output, the value actually set.
> + @param Timeout The requested time out for a single character in
> microseconds.
> + This timeout applies to both the transmit and receive side of
> the
> + interface. A Timeout value of 0 will use the device's default
> time
> + out value.
> + On output, the value actually set.
> + @param Parity The type of parity to use on this serial device. A Parity
> value of
> + DefaultParity will use the device's default parity value.
> + On output, the value actually set.
> + @param DataBits The number of data bits to use on the serial device.
> A DataBits
> + vaule of 0 will use the device's default data bit setting.
> + On output, the value actually set.
> + @param StopBits The number of stop bits to use on this serial device.
> A StopBits
> + value of DefaultStopBits will use the device's default number
> of
> + stop bits.
> + On output, the value actually set.
> +
> + @retval RETURN_SUCCESS The new attributes were set on the serial
> device.
> + @retval RETURN_UNSUPPORTED The serial device does not support
> this operation.
> + @retval RETURN_INVALID_PARAMETER One or more of the attributes has
> an unsupported value.
> + @retval RETURN_DEVICE_ERROR The serial device is not functioning
> correctly.
> +
> +**/
> +RETURN_STATUS
> +EFIAPI
> +SerialPortSetAttributes (
> + IN OUT UINT64 *BaudRate,
> + IN OUT UINT32 *ReceiveFifoDepth,
> + IN OUT UINT32 *Timeout,
> + IN OUT EFI_PARITY_TYPE *Parity,
> + IN OUT UINT8 *DataBits,
> + IN OUT EFI_STOP_BITS_TYPE *StopBits
> + )
> +{
> + UINTN BaseAddress;
> + BOOLEAN UseMmio;
> + UINT32 SerialBaudRate;
> + UINTN Divisor;
> + UINT8 Lcr;
> + UINT8 LcrData;
> + UINT8 LcrParity;
> + UINT8 LcrStop;
> + UINT8 Count;
> + UINT8 Stride;
> +
> + Count = 0;
> + while (Count < mUartCount) {
> + BaseAddress = mUartInfo[Count]->BaseAddress;
> + UseMmio = mUartInfo[Count]->UseMmio;
> + Stride = mUartInfo[Count]->RegisterStride;
> +
> + if (BaseAddress == 0) {
> + return RETURN_UNSUPPORTED;
> + }
> +
> + //
> + // Check for default settings and fill in actual values.
> + //
> + if (*BaudRate == 0) {
> + *BaudRate = mUartInfo[Count]->BaudRate;
> + }
> +
> + SerialBaudRate = (UINT32)*BaudRate;
> +
> + if (*DataBits == 0) {
> + LcrData = (UINT8)(PcdGet8 (PcdSerialLineControl) & 0x3);
> + *DataBits = LcrData + 5;
> + } else {
> + if ((*DataBits < 5) || (*DataBits > 8)) {
> + return RETURN_INVALID_PARAMETER;
> + }
> +
> + //
> + // Map 5..8 to 0..3
> + //
> + LcrData = (UINT8)(*DataBits - (UINT8)5);
> + }
> +
> + if (*Parity == DefaultParity) {
> + LcrParity = (UINT8)((PcdGet8 (PcdSerialLineControl) >> 3) & 0x7);
> + switch (LcrParity) {
> + case 0:
> + *Parity = NoParity;
> + break;
> +
> + case 3:
> + *Parity = EvenParity;
> + break;
> +
> + case 1:
> + *Parity = OddParity;
> + break;
> +
> + case 7:
> + *Parity = SpaceParity;
> + break;
> +
> + case 5:
> + *Parity = MarkParity;
> + break;
> +
> + default:
> + break;
> + }
> + } else {
> + switch (*Parity) {
> + case NoParity:
> + LcrParity = 0;
> + break;
> +
> + case EvenParity:
> + LcrParity = 3;
> + break;
> +
> + case OddParity:
> + LcrParity = 1;
> + break;
> +
> + case SpaceParity:
> + LcrParity = 7;
> + break;
> +
> + case MarkParity:
> + LcrParity = 5;
> + break;
> +
> + default:
> + return RETURN_INVALID_PARAMETER;
> + }
> + }
> +
> + if (*StopBits == DefaultStopBits) {
> + LcrStop = (UINT8)((PcdGet8 (PcdSerialLineControl) >> 2) & 0x1);
> + switch (LcrStop) {
> + case 0:
> + *StopBits = OneStopBit;
> + break;
> +
> + case 1:
> + if (*DataBits == 5) {
> + *StopBits = OneFiveStopBits;
> + } else {
> + *StopBits = TwoStopBits;
> + }
> +
> + break;
> +
> + default:
> + break;
> + }
> + } else {
> + switch (*StopBits) {
> + case OneStopBit:
> + LcrStop = 0;
> + break;
> +
> + case OneFiveStopBits:
> + case TwoStopBits:
> + LcrStop = 1;
> + break;
> +
> + default:
> + return RETURN_INVALID_PARAMETER;
> + }
> + }
> +
> + //
> + // Calculate divisor for baud generator
> + // Ref_Clk_Rate / Baud_Rate / 16
> + //
> + Divisor = PcdGet32 (PcdSerialClockRate) / (SerialBaudRate * 16);
> + if ((PcdGet32 (PcdSerialClockRate) % (SerialBaudRate * 16)) >=
> SerialBaudRate * 8) {
> + Divisor++;
> + }
> +
> + //
> + // Configure baud rate
> + //
> + SerialPortWriteRegister (BaseAddress, R_UART_LCR, B_UART_LCR_DLAB,
> UseMmio, Stride);
> + SerialPortWriteRegister (BaseAddress, R_UART_BAUD_HIGH,
> (UINT8)(Divisor >> 8), UseMmio, Stride);
> + SerialPortWriteRegister (BaseAddress, R_UART_BAUD_LOW,
> (UINT8)(Divisor & 0xff), UseMmio, Stride);
> +
> + //
> + // Clear DLAB and configure Data Bits, Parity, and Stop Bits.
> + // Strip reserved bits from line control value
> + //
> + Lcr = (UINT8)((LcrParity << 3) | (LcrStop << 2) | LcrData);
> + SerialPortWriteRegister (BaseAddress, R_UART_LCR, (UINT8)(Lcr & 0x3F),
> UseMmio, Stride);
> + Count++;
> + }
> +
> + return RETURN_SUCCESS;
> +}
> diff --git
> a/UefiPayloadPkg/Library/BaseSerialPortLibHob/BaseSerialPortLibHob.inf
> b/UefiPayloadPkg/Library/BaseSerialPortLibHob/BaseSerialPortLibHob.inf
> new file mode 100644
> index 0000000000..1dbe107dbd
> --- /dev/null
> +++
> b/UefiPayloadPkg/Library/BaseSerialPortLibHob/BaseSerialPortLibHob.inf
> @@ -0,0 +1,40 @@
> +## @file
> +# SerialPortLib instance for UART information retrieved from bootloader.
> +#
> +# Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
> +#
> +# SPDX-License-Identifier: BSD-2-Clause-Patent
> +#
> +##
> +
> +[Defines]
> + INF_VERSION = 0x00010005
> + BASE_NAME = BaseSerialPortLibHob
> + FILE_GUID = d8d22930-e8ec-469f-8184-5a069149b2ff
> + MODULE_TYPE = BASE
> + VERSION_STRING = 1.0
> + LIBRARY_CLASS = SerialPortLib
> +
> +[Packages]
> + MdePkg/MdePkg.dec
> + MdeModulePkg/MdeModulePkg.dec
> +
> +[LibraryClasses]
> + PcdLib
> + IoLib
> + HobLib
> + TimerLib
> + MemoryAllocationLib
> +
> +[Sources]
> + BaseSerialPortLibHob.c
> +
> +[Pcd]
> + gEfiMdeModulePkgTokenSpaceGuid.PcdSerialLineControl
> + gEfiMdeModulePkgTokenSpaceGuid.PcdSerialFifoControl
> + gEfiMdeModulePkgTokenSpaceGuid.PcdSerialClockRate
> + gEfiMdeModulePkgTokenSpaceGuid.PcdSerialExtendedTxFifoSize
> + gEfiMdeModulePkgTokenSpaceGuid.PcdSerialUseHardwareFlowControl
> +
> +[Guids]
> + gUniversalPayloadSerialPortInfoGuid
> --
> 2.30.2.windows.1
^ permalink raw reply [flat|nested] 3+ messages in thread
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